diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index f843ba4..4163fdb 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -890,106 +890,32 @@
     ContextCU->addDIEEntry(*AbsDef, dwarf::DW_AT_object_pointer, *ObjectPointer);
 }
 
-dwarf::Tag DwarfCompileUnit::getDwarf5OrGNUCallSiteTag(dwarf::Tag Tag) {
-  bool ApplyGNUExtensions = DD->getDwarfVersion() == 4 && DD->tuneForGDB();
-  if (!ApplyGNUExtensions)
-    return Tag;
-  switch (Tag) {
-  case dwarf::DW_TAG_call_site:
-    return dwarf::DW_TAG_GNU_call_site;
-  case dwarf::DW_TAG_call_site_parameter:
-    return dwarf::DW_TAG_GNU_call_site_parameter;
-  default:
-    llvm_unreachable("unhandled call site tag");
-  }
-}
-
-dwarf::Attribute
-DwarfCompileUnit::getDwarf5OrGNUCallSiteAttr(dwarf::Attribute Attr) {
-  bool ApplyGNUExtensions = DD->getDwarfVersion() == 4 && DD->tuneForGDB();
-  if (!ApplyGNUExtensions)
-    return Attr;
-  switch (Attr) {
-  case dwarf::DW_AT_call_all_calls:
-    return dwarf::DW_AT_GNU_all_call_sites;
-  case dwarf::DW_AT_call_target:
-    return dwarf::DW_AT_GNU_call_site_target;
-  case dwarf::DW_AT_call_origin:
-    return dwarf::DW_AT_abstract_origin;
-  case dwarf::DW_AT_call_pc:
-    return dwarf::DW_AT_low_pc;
-  case dwarf::DW_AT_call_value:
-    return dwarf::DW_AT_GNU_call_site_value;
-  case dwarf::DW_AT_call_tail_call:
-    return dwarf::DW_AT_GNU_tail_call;
-  default:
-    llvm_unreachable("unhandled call site attribute");
-  }
-}
-
-DIE &DwarfCompileUnit::constructCallSiteEntryDIE(
-    DIE &ScopeDIE, const DISubprogram *CalleeSP, bool IsTail,
-    const MCSymbol *PCAddr, const MCExpr *PCOffset, unsigned CallReg) {
+DIE &DwarfCompileUnit::constructCallSiteEntryDIE(DIE &ScopeDIE,
+                                                 const DISubprogram &CalleeSP,
+                                                 bool IsTail,
+                                                 const MCExpr *PCOffset) {
   // Insert a call site entry DIE within ScopeDIE.
-  DIE &CallSiteDIE = createAndAddDIE(
-      getDwarf5OrGNUCallSiteTag(dwarf::DW_TAG_call_site), ScopeDIE, nullptr);
+  DIE &CallSiteDIE =
+      createAndAddDIE(dwarf::DW_TAG_call_site, ScopeDIE, nullptr);
 
-  if (CallReg) {
-    // Indirect call.
-    addAddress(CallSiteDIE,
-               getDwarf5OrGNUCallSiteAttr(dwarf::DW_AT_call_target),
-               MachineLocation(CallReg));
-  } else {
-    DIE *CalleeDIE = getOrCreateSubprogramDIE(CalleeSP);
-    assert(CalleeDIE && "Could not create DIE for call site entry origin");
-    addDIEEntry(CallSiteDIE,
-                getDwarf5OrGNUCallSiteAttr(dwarf::DW_AT_call_origin),
-                *CalleeDIE);
-  }
+  // For the purposes of showing tail call frames in backtraces, a key piece of
+  // information is DW_AT_call_origin, a pointer to the callee DIE.
+  DIE *CalleeDIE = getOrCreateSubprogramDIE(&CalleeSP);
+  assert(CalleeDIE && "Could not create DIE for call site entry origin");
+  addDIEEntry(CallSiteDIE, dwarf::DW_AT_call_origin, *CalleeDIE);
 
-  if (IsTail)
+  if (IsTail) {
     // Attach DW_AT_call_tail_call to tail calls for standards compliance.
-    addFlag(CallSiteDIE,
-            getDwarf5OrGNUCallSiteAttr(dwarf::DW_AT_call_tail_call));
-
-  // Attach the return PC to allow the debugger to disambiguate call paths
-  // from one function to another.
-  if (DD->getDwarfVersion() == 4 && DD->tuneForGDB()) {
-    assert(PCAddr && "Missing PC information for a call");
-    addLabelAddress(CallSiteDIE, dwarf::DW_AT_low_pc, PCAddr);
-  } else if (!IsTail || DD->tuneForGDB()) {
+    addFlag(CallSiteDIE, dwarf::DW_AT_call_tail_call);
+  } else {
+    // Attach the return PC to allow the debugger to disambiguate call paths
+    // from one function to another.
     assert(PCOffset && "Missing return PC information for a call");
     addAddressExpr(CallSiteDIE, dwarf::DW_AT_call_return_pc, PCOffset);
   }
-
   return CallSiteDIE;
 }
 
-void DwarfCompileUnit::constructCallSiteParmEntryDIEs(
-    DIE &CallSiteDIE, SmallVector<DbgCallSiteParam, 4> &Params) {
-  for (auto &Param : Params) {
-    unsigned Register = Param.getRegister();
-    auto CallSiteDieParam =
-        DIE::get(DIEValueAllocator,
-                 getDwarf5OrGNUCallSiteTag(dwarf::DW_TAG_call_site_parameter));
-    insertDIE(CallSiteDieParam);
-    addAddress(*CallSiteDieParam, dwarf::DW_AT_location,
-               MachineLocation(Register));
-
-    DIELoc *Loc = new (DIEValueAllocator) DIELoc;
-    DIEDwarfExpression DwarfExpr(*Asm, *this, *Loc);
-    DwarfExpr.setCallSiteParamValueFlag();
-
-    DwarfDebug::emitDebugLocValue(*Asm, nullptr, Param.getValue(), DwarfExpr);
-
-    addBlock(*CallSiteDieParam,
-             getDwarf5OrGNUCallSiteAttr(dwarf::DW_AT_call_value),
-             DwarfExpr.finalize());
-
-    CallSiteDIE.addChild(CallSiteDieParam);
-  }
-}
-
 DIE *DwarfCompileUnit::constructImportedEntityDIE(
     const DIImportedEntity *Module) {
   DIE *IMDie = DIE::get(DIEValueAllocator, (dwarf::Tag)Module->getTag());